1 files changed, 278 insertions, 0 deletions
diff --git a/lib/libgpio/gpio.c b/lib/libgpio/gpio.c
new file mode 100644
index 0000000..7ec0955
--- /dev/null
+++ b/lib/libgpio/gpio.c
@@ -0,0 +1,278 @@
+/*-
+ * Copyright (c) 2013-2014 Rui Paulo <rpaulo@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <sys/ioctl.h>
+#include <sys/types.h>
+
+#include <libgpio.h>
+
+gpio_handle_t
+gpio_open(unsigned int unit)
+{
+	char device[16];
+
+	snprintf(device, sizeof(device), "/dev/gpioc%u", unit);
+
+	return (gpio_open_device(device));
+}
+
+gpio_handle_t
+gpio_open_device(const char *device)
+{
+	int fd, maxpins;
+	int serr;
+
+	fd = open(device, O_RDONLY);
+	if (fd < 0)
+		return (GPIO_INVALID_HANDLE);
+	/*
+	 * Check whether a simple ioctl works.
+	 */
+	if (ioctl(fd, GPIOMAXPIN, &maxpins) < 0) {
+		serr = errno;
+		close(fd);
+		errno = serr;
+		return (GPIO_INVALID_HANDLE);
+	}
+
+	return (fd);
+}
+
+void
+gpio_close(gpio_handle_t handle)
+{
+	close(handle);
+}
+
+int
+gpio_pin_list(gpio_handle_t handle, gpio_config_t **pcfgs)
+{
+	int maxpins, i;
+	gpio_config_t *cfgs;
+
+	*pcfgs = NULL;
+	if (ioctl(handle, GPIOMAXPIN, &maxpins) < 0)
+		return (-1);
+	/* Reasonable values. */
+	if (maxpins < 0 || maxpins > 4096) {
+		errno = EINVAL;
+		return (-1);
+	}
+	cfgs = calloc(maxpins + 1, sizeof(*cfgs));
+	if (cfgs == NULL)
+		return (-1);
+	for (i = 0; i <= maxpins; i++) {
+		cfgs[i].g_pin = i;
+		gpio_pin_config(handle, &cfgs[i]);
+	}
+	*pcfgs = cfgs;
+
+	return (maxpins);
+}
+
+int
+gpio_pin_config(gpio_handle_t handle, gpio_config_t *cfg)
+{
+	struct gpio_pin gppin;
+
+	if (cfg == NULL)
+		return (-1);
+	gppin.gp_pin = cfg->g_pin;
+	if (ioctl(handle, GPIOGETCONFIG, &gppin) < 0)
+		return (-1);
+	strlcpy(cfg->g_name, gppin.gp_name, GPIOMAXNAME);
+	cfg->g_caps = gppin.gp_caps;
+	cfg->g_flags = gppin.gp_flags;
+
+	return (0);
+}
+
+int
+gpio_pin_set_name(gpio_handle_t handle, gpio_pin_t pin, char *name)
+{
+	struct gpio_pin gppin;
+
+	if (name == NULL)
+		return (-1);
+	bzero(&gppin, sizeof(gppin));
+	gppin.gp_pin = pin;
+	strlcpy(gppin.gp_name, name, GPIOMAXNAME);
+	if (ioctl(handle, GPIOSETNAME, &gppin) < 0)
+		return (-1);
+
+	return (0);
+}
+
+int
+gpio_pin_set_flags(gpio_handle_t handle, gpio_config_t *cfg)
+{
+	struct gpio_pin gppin;
+
+	if (cfg == NULL)
+		return (-1);
+	gppin.gp_pin = cfg->g_pin;
+	gppin.gp_flags = cfg->g_flags;
+	if (ioctl(handle, GPIOSETCONFIG, &gppin) < 0)
+		return (-1);
+
+	return (0);
+}
+
+gpio_value_t
+gpio_pin_get(gpio_handle_t handle, gpio_pin_t pin)
+{
+	struct gpio_req gpreq;
+
+	bzero(&gpreq, sizeof(gpreq));
+	gpreq.gp_pin = pin;
+	if (ioctl(handle, GPIOGET, &gpreq) < 0)
+		return (GPIO_VALUE_INVALID);
+
+	return (gpreq.gp_value);
+}
+
+int
+gpio_pin_set(gpio_handle_t handle, gpio_pin_t pin, gpio_value_t value)
+{
+	struct gpio_req gpreq;
+
+	if (value == GPIO_VALUE_INVALID)
+		return (-1);
+	bzero(&gpreq, sizeof(gpreq));
+	gpreq.gp_pin = pin;
+	gpreq.gp_value = value;
+	if (ioctl(handle, GPIOSET, &gpreq) < 0)
+		return (-1);
+
+	return (0);
+}
+
+int
+gpio_pin_toggle(gpio_handle_t handle, gpio_pin_t pin)
+{
+	gpio_value_t value;
+
+	value = gpio_pin_get(handle, pin);
+	if (value == GPIO_VALUE_INVALID)
+		return (-1);
+	value = !value;
+
+	return (gpio_pin_set(handle, pin, value));
+}
+
+int
+gpio_pin_low(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set(handle, pin, GPIO_VALUE_LOW));
+}
+
+int
+gpio_pin_high(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set(handle, pin, GPIO_VALUE_HIGH));
+}
+
+static int
+gpio_pin_set_flag(gpio_handle_t handle, gpio_pin_t pin, uint32_t flag)
+{
+	gpio_config_t cfg;
+
+	bzero(&cfg, sizeof(cfg));
+	cfg.g_pin = pin;
+	if (gpio_pin_config(handle, &cfg) < 0)
+		return (-1);
+	cfg.g_flags = flag;
+
+	return (gpio_pin_set_flags(handle, &cfg));
+}
+
+int
+gpio_pin_input(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_INPUT));
+}
+
+int
+gpio_pin_output(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_OUTPUT));
+}
+
+int
+gpio_pin_opendrain(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_OPENDRAIN));
+}
+
+int
+gpio_pin_pushpull(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_PUSHPULL));
+}
+
+int
+gpio_pin_tristate(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_TRISTATE));
+}
+
+int
+gpio_pin_pullup(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_PULLUP));
+}
+
+int
+gpio_pin_pulldown(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_PULLDOWN));
+}
+
+int
+gpio_pin_invin(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_INVIN));
+}
+
+int
+gpio_pin_invout(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_INVOUT));
+}
+
+int
+gpio_pin_pulsate(gpio_handle_t handle, gpio_pin_t pin)
+{
+	return (gpio_pin_set_flag(handle, pin, GPIO_PIN_PULSATE));
+}